Hey all! I don't know much of the history of my new '86 california 4runner but been fixing it up.

The issue now is misfiring / low idle

1) New spark plugs and wires - no change
2) Adjusted TPS / cleaned idle screw (it was real sooty) / adjusted throttle cable - Now seems to not misfire anymore, but idle is still low. note: The TPS was almost good but still off. I'm pretty sure that's what did it.

BUT now it still idles low and the screw won't get it any higher.

One thing I've noticed is that there's a loud hissing sound coming from around the EFI. Sounds like a lot of air escaping a tube or something. Like a pretty noticeable (loud enough to hear very well over the engine) blowing sound. I'm going to be replacing the vacuum lines, but i can't see where this sound is coming from. Any suggestions?

Also the idle screw o-ring is super hard. I thought it was just a basic o-ring, but it feels rock hard to the touch. Is it just old or is it supposed to be hard? Can I just pull it and put in any rubber o-ring that fits? I tried prying at it with a small flathead but it wouldn't budge so I thought I'd check with you guys before ripping it out.

 

The hissing is normal. What is "low idle"? Is your tach working correctly? measure actual idle RPMs with a laser or LED unit. 19,95 on the web.

 

 

This Toyota o-ring fits perfect: 90301-07001

 

Take a crisp new dollar bill and hold it as close as you can get it to the end of your exhaust pipe...
if every now and then it sucks it to the exhaust pipe and kinda pops... you have a leaking valve...
adjust the valves and some of the low idle miss will go away...

 

OOOkkkk so it does suck that dolla into the pipe here and there.

Also wanted to add that it usually starts up smooth when cold, then it takes a few seconds (like 5-10 seconds) before it starts acting up.

Is there anything besides the valves that could cause the sucking? I had done a quick look at the valves and they didn't seem very off, but I guess I'll check closer.

As for adjusting them, the COLD or HOT discussion... this might open a can of worms, but what would you suggest? 22re performance website suggests cold since it's more consistent, I feel like they would know their ˟˟˟˟˟...

 

Also, forgot to add that the timing is adjusted by hand and ear. I just adjusted it to what sounds best and misfires less with these not best conditions... so that might lead to this too?

 

Ok so i changed the idle screw o-ring, adjusted the valves and properly set timing, made a world of difference!

Now I can listen to a proper valve orchestra! All the valve spacings were too tight, to the point where, yes, i suspect exhaust may have had trouble closing all the way

I did it as per the manual, hot engine. Will probably do it again in a few weeks or so just to check up on it.

Thanks for the tips!